Methods and apparatus for mixing fluid in turbine engines

Abstract

A method of assembling a gas turbine engine includes providing at least one heat exchanger assembly including a heat exchanger and a lobed mixer extending downstream from the heat exchanger, wherein the mixer includes a plurality of lobes that each define a first chute and at least one second chute that extends between each pair of adjacent spaced-apart lobes, and coupling the at least one heat exchanger assembly within a bypass duct of the engine such that the at least one heat exchanger assembly is coupled to at least one of an outer engine casing and an inner engine casing of the turbine engine.

What is claimed is: 
     
       1. A method of assembling a gas turbine engine, said method comprising:
 providing at least one heat exchanger assembly including a heat exchanger and a lobed mixer coupled to the heat exchanger and extending downstream from the heat exchanger, wherein the mixer includes a plurality of lobes on multiple sides of the mixer, wherein each lobe define a first chute and at least one second chute that extends between each pair of adjacent spaced-apart lobes; and 
 coupling the at least one heat exchanger assembly within a bypass duct of the engine such that a first portion of bypass air flows above and below said at least one heat exchanger and the mixer within the bypass duct, while a second portion of bypass air flows through said at least one heat exchanger, wherein the first and second portions of bypass air communicate at said plurality of lobes on said multiple sides of the mixer; wherein the at least one heat exchanger assembly is coupled to at least one of an outer engine casing and an inner engine casing of the turbine engine. 
 
     
     
       2. A method in accordance with  claim 1  wherein providing at least one heat exchanger assembly further comprises providing a heat exchanger that includes a hollow body and a plurality of heat exchanger fins within the body. 
     
     
       3. A method in accordance with  claim 2  wherein the mixer is in flow communication with a cavity defined within the hollow body. 
     
     
       4. A method in accordance with  claim 2  wherein each first chute extends divergently outward from a downstream side of the heat exchanger assembly and such that each second chute extends convergently inward from the downstream side of the heat exchanger assembly. 
     
     
       5. A method in accordance with  claim 1  wherein coupling the at least one heat exchanger assembly further comprises orienting the at least one heat exchanger assembly within the bypass duct to facilitate reducing pressure losses within the bypass airflow. 
     
     
       6. A method in accordance with  claim 1  wherein an inlet of the mixer is coupled to an outlet of the heat exchanger assembly and an outlet of the mixer has a cross-sectional area that is larger than a cross-sectional area of the mixer inlet. 
     
     
       7. A method in accordance with  claim 1  wherein the at least one heat exchanger includes an inlet having a cross-sectional area that is smaller than a cross-sectional area of an outlet of the mixer. 
     
     
       8. A heat exchanger assembly for use in a turbine engine, said heat exchanger assembly comprising:
 at least one core heat exchanger configured to be coupled within a bypass duct of the engine, said at least one core heat exchanger including an inlet, an outlet, a hollow body and a plurality of heat exchanger fins that extend at least partially through the hollow body between the inlet and the outlet, said at least one core heat exchanger configured to be positioned within the duct such that a first portion of bypass air flows above and below said at least one core heat exchanger while a second portion of bypass air flows through said at least one core heat exchanger; and 
 a mixer coupled to said at least one core heat exchanger and extending downstream from said at least one core heat exchanger, said mixer comprising a plurality of lobes on multiple sides of the mixer, wherein each lobe defines a first chute, wherein said plurality of lobes are spaced about an outer perimeter on multiple sides of said mixer such that at least one second chute is defined between each pair of adjacent spaced-apart lobes. 
 
     
     
       9. A heat exchanger assembly in accordance with  claim 8  wherein said mixer extends from said at least one core heat exchanger outlet, such that said mixer is in flow communication with a cavity defined within said body. 
     
     
       10. A heat exchanger assembly in accordance with  claim 8  wherein said mixer further comprises:
 an inlet having a first cross-sectional area; 
 an outlet having a second cross-sectional area that is larger than said first cross-sectional area; and 
 a mixer body extending between said inlet and said outlet. 
 
     
     
       11. A heat exchanger assembly in accordance with  claim 10  wherein said mixer outlet facilitates increasing an amount of air entrained within said at least one heat exchanger assembly. 
     
     
       12. A heat exchanger assembly in accordance with  claim 10  wherein a portion of said mixer extends divergently downstream from said at least one core heat exchanger. 
     
     
       13. A gas turbine engine comprising:
 an outer casing, 
 an inner casing, 
 a bypass duct defined between said outer casing and said inner casing, the bypass duct defining an airflow path; and 
 at least one heat exchanger assembly coupled within said bypass duct to at least one of said outer casing and said inner casing, said at least one heat exchanger assembly comprising:
 at least one heat exchanger disposed at least partially within said airflow path; and 
 a mixer coupled to said at least one heat exchanger such that a first portion of bypass air flows above and below said at least one heat exchanger and said mixer within said bypass duct, while a second portion of bypass air flows through said at least one heat exchanger, said mixer comprising a plurality of lobes on multiple sides of said mixer, wherein each lobe defines a first chute, said plurality of lobes spaced about a perimeter of said mixer such that a second chute is defined between each pair of adjacent spaced-apart lobes, wherein the first and second portions of bypass air communicate at said plurality of lobes on said multiple sides of said mixer. 
 
 
     
     
       14. A gas turbine engine in accordance with  claim 13  wherein said at least one heat exchanger assembly comprises:
 an inlet, an outlet, and a hollow body extending therebetween; and 
 a plurality of heat exchanger fins extending at least partially through said body between said inlet and said outlet. 
 
     
     
       15. A gas turbine engine in accordance with  claim 14  wherein said mixer extends downstream from said outlet and is in flow communication with a cavity defined within said body. 
     
     
       16. A gas turbine engine in accordance with  claim 13  wherein said mixer further comprises:
 an inlet having a first cross-sectional area; 
 an outlet having a second cross-sectional area that is larger than said inlet cross-sectional area; and 
 a hollow body extending between said inlet and said outlet. 
 
     
     
       17. A gas turbine engine in accordance with  claim 16  wherein said mixer outlet facilitates increasing an amount of air entrained within said at least one heat exchanger assembly. 
     
     
       18. A gas turbine engine in accordance with  claim 16  wherein each of said first chutes diverge generally outward downstream from said at least one heat exchanger assembly, and each of said second chutes converges generally inward downstream from said at least one heat exchanger assembly. 
     
     
       19. A gas turbine engine in accordance with  claim 13  wherein said mixer facilitates reducing pressure losses downstream from said at least one heat exchanger assembly.